data {
  int<lower=0> N;
  int<lower=0,upper=1> useforce[N];
  vector[N] igo_lev3_count_use_bc;
  vector[N] salint;
  vector[N] saltan;
  vector[N] terriss;
  vector[N] jointpol7;
  vector[N] rivalry_th;
  vector[N] absidealdiff;
  vector[N] atopally;
}
parameters {
  vector[9] beta;
}
model {

  for (k in 1:9)
        beta[k] ~ student_t(7, 0, 2.5);

  useforce ~ bernoulli(Phi(beta[1] + beta[2] * igo_lev3_count_use_bc 
                             + beta[3] * salint
                             + beta[4] * saltan
                             + beta[5] * terriss
                             + beta[6] * jointpol7
                             + beta[7] * rivalry_th
                             + beta[8] * absidealdiff
                             + beta[9] * atopally));
}